Growth models (GM) of the mixed-effects and latent curve varieties have become popular methodological tools in lifespan research. One of the major advantages of GM is their flexibility in studying individual differences in change. We scrutinized the change functions of GM used in five years of publications on cognitive aging. Of the 162…

First-order theory of mind (ToM) development has shown to conform to a Guttman scale, with desire reasoning developing before belief reasoning. There have been attempts to test for internal consistency and scalability in advanced ToM, but not over a broad age range and only with a limited set of tasks. This 2-year longitudinal study (N = 155;…

Listening to speech in a noisy background is difficult for everyone. While such listening has historically been considered mainly in the context of auditory processing, the role of cognition has attracted considerable interest in recent years. This has been particularly true in the context of life-span research and the comparison of younger and…

Most of the individual difference variance in the population is found "within" families, yet studying the processes causing this variation is difficult due to confounds between genetic and nongenetic influences. Quasi-experiments can be used to test hypotheses regarding environment exposure (e.g., timing, duration) while controlling for…

Describes how three-year-olds regulate their effort during competition and compares their facial expressions after failure and success, demonstrating the operation of a display rule in competition. Explores the cross-situational stability of subjects' regulation of behavior, as well as the relationship between factors influencing mother-child…